Felicity conditions

In J.L. Austin's formulation of Speech act theory, a performative utterance is neither true nor false, but can instead be deemed "felicitous" or "infelicitous" according to a set of conditions whose interpretation differs depending on whether the utterance in question is a declaration ("I sentence you to death"), a request ("I ask that you stop doing that") or a warning ("I warn you not to jump off the roof").